The invention relates to apparatus and methods for delivering fluids to a patient and, more particularly, to apparatus and methods for peritoneal dialysis (PD). It has application, inter alia, in the delivery of PD solution to a patient, for example, during automated peritoneal dialysis (APD) procedures.
Peritoneal dialysis (PD) is a medical procedure for removing toxins from the blood that takes advantage of the semi-permeable membrane surrounding the walls of the abdomen or peritoneal cavity. During a PD procedure, a solution is introduced into the patient's abdomen, where it remains for up to several hours, removing blood toxins via osmotic transfer through that membrane. At completion of the procedure, the solution is drained from the body along with the toxins. In APD, the entire procedure is handled by automated equipment.
There are many systems on the market today for performing APD. Typically, such systems include a pumps and a variety of other complex components. In today's economy, cost is an ever-increasing issue, and PD equipment manufacturers have attempted to reduce production costs by several means. One is to employ peristaltic pumps, which can be inexpensive, though, they have inherent limitations. For example, accurately measuring the fluid volume delivered by a peristaltic pump can be difficult, e.g., because the tubing in the pump loses elasticity and, consequently, its volume changes over time. PD pumps also tend to develop pinhole leaks in pump tubing.
An object of the invention is to provide improved methods and apparatus for delivering fluid to a patient.
A further object of the invention is to provide such improved methods and apparatus for delivering PD solutions to a patient.
A still further object is to provide such improved methods and apparatus as can be adapted for using conventional pump technologies, e.g., peristaltic pumps.
A still further object of the invention is to provide such methods and apparatus as can be implemented at reasonable cost, yet, produce efficacious results.